Rovnoscydmus

Jałoszyński, Paweł & Perkovsky, Evgeny, 2016, Diversity of Scydmaeninae (Coleoptera: Staphylinidae) in Upper Eocene Rovno amber, Zootaxa 4157 (1), pp. 1-85 : 52

† Rovnoscydmus sp. specimen 8

( Figs 21 , 155–160 )

Material studied. Late Eocene of Europe , Rovno amber: sex unknown; inclusion in elongate, trapezoidal prism of amber 12 mm long ( Fig. 21 ), collection number K-8972 ( SIZK).

Description. Body ( Figs 155, 157, 158, 160 ) elongate, slender and relatively strongly convex, dark brown; BL 1.08 mm.

Head ( Figs 156, 159 ) broadest at eyes, HL 0.20 mm, HW 0.18 mm; vertex and frons confluent, together subtrapezoidal and nearly as long as broad; supraantennal tubercles indistinct; compound eyes large, strongly convex, oval; tempora slightly longer than eyes. Punctures and setae on frons and vertex poorly visible, but short and sparse bristles can be seen on tempora ( Fig. 159 ). Antennae ( Figs 156, 159 ) distinctly shorter than half BL, AnL 0.48 mm, antennal club indistinctly demarcated; antennomeres I–II strongly elongate, III–VIII elongate (at least weakly), IX slightly transverse, X about as long as broad, XI much shorter than IX–X combined, about 1.2 × as long as broad, with rounded apex.

Pronotum poorly visible, broadest site not possible to define; PL 0.25 mm, PW 0.25 mm; punctures and setae not visible.

Elytra ( Figs 155, 158 ) elongate oval, strongly convex, broadest site not possible to define, EL 0.63 mm, EW 0.40 mm, EI 1.56; punctures ( Fig. 158 ) fine, separated by spaces about 3 × as wide as diameters of punctures; setae ( Fig. 158 ) short, sparse, nearly recumbent.

Legs ( Figs 157, 160 ) moderately long, slender, unmodified.

Remarks. The pronotum of this specimen is only partly visible, but the shape of the head, structure of the antenna and ventral pterothoracic structures strongly suggest that this is Rovnoscydmus . The well-exposed anterior portion of the mesoventrite is especially interesting, as it shows clearly the lateral setose impressions functioning as procoxal rests ( Fig. 160 ; pcr) and the median projection of anterior ridge separating the impressions at middle. This inclusion may be conspecific with Rovnoscydmus specimens 4, 5 and? Rovnoscydmus specimen 10, as they were all found in one piece of amber.

Figures

FIGURES 21 – 34. Specimens of Rovno amber with inclusions of Scydmaeninae. K- 8972, Rovnoscydmus sp. specimen 8 (21); K- 3322, Rovnoscydmus sp. specimen 9 (22); K- 15548,? Rovnoscydmus sp. specimen 10 (23); K- 8971,? Rovnoscydmus sp. specimen 11 (24); K- 6045, Euconnus palaeogenus sp. n. (25); K- 9126, Euconnus sp. 1 (26); K- 24859,? Euconnus sp. 2 (27); K- 24302, Stenichnus proavus sp. n. (28); UA- 2216, Microscydmus sp. 1 (29); K- 6943,? Microscydmus sp. 2 (30); K- 3657 a,? Microscydmus sp. 3 (31); K- 6764,? Scydmoraphes sp. 1 (32); K- 6274, Glandulariini gen. & sp. indet. 1 (33); K- 7089, Glandulariini gen. & sp. indet. 2 (34).

FIGURES 155 – 160. Rovnoscydmus sp. specimen 8 (K- 8972). Dorsolateral (155, 158) and ventral (157, 160) views, and head in dorsal view (156, 159). Abbreviations: fr, frons; mcp, mesocoxal projection; md, mandible; mtvp, metaventral intercoxal process; mxp 2 – 4, maxillary palpomere II – IV; nr, ' neck' region; occ, occipital constriction; pcr, procoxal rest; st 3 – 8, abdominal sternite III – VIII; tm, temple; v 3, metaventrite; vt, vertex.